27 Responses to “Announcements/Q & A”

Hi Andrew. I’ve enjoyed your blog for a while. Now I’m looking for a home to buy and find myself wondering if YOU would buy (or even rent) in Sheffield Village? It’s one of the areas our budget has led us to, but it scares me. And then I wonder if living ON the fault is so much worse than living, say, across the freeway from the fault.
Thanks!
Lesley

[Lesley, I’m not a practicing geologist and it would be illegal for me to advise you. I can only tell you that I live less than 2 kilometers from the fault, love where I am, and am not a homeowner. I can also tell you that I adore Sheffield Village. Every homesite has its own unique geologic setting, even within a single development.

[The concentric brown bands inside massive sandstone are common in coastal California. I understand that they mark the passage of petroleum from source beds below on their way toward the surface or an underground trap. They are spectacularly exposed along the Santa Cruz beach cliffs among other places. –Andrew]

Next weekSaturday the 18thI’ll be leading a walk for the Oakland Heritage Alliance down at Middle Harbor Park, 10 am to noon. The topic is the wonderful recycled landscape there, regarded as both an artistic and geotechnical achievement.

There may be a Cretaceous/Tertiary contact exposure near the San Leandro Reservoir. Do you know anything about it?

-Michael Greene

[Michael, the contact is mapped as a thrust fault, with the Cretaceous rocks pushed over the younger ones. Moreover, the Cretaceous rocks are of Campanian age while the Tertiary rocks are Miocene, so there’s an age gap of about 50 million years there.

The nearest true K-T (Maastrichtian–Danian) contact I know of is down in the Panoche Hills.]

On Saturday 31 August I will be leading a walk along the Hayward fault at the foot of Claremont Canyon for the Claremont Canyon Conservancy. There’s no announcement on the website. We start at 10 a.m. at the top of Dwight Way, at Fernwald Road, and will finish before noon.

Andrew — Do you know anything about Sheridan Road in upper Rockridge (see http://goo.gl/maps/2vYPJ and http://goo.gl/maps/rY2m7 ) ? The road appears to have slid away at some point, but the right of way still exists. I’m suggesting that the trail over the ROW be included in an Oakland Urban Paths walk at some point, and it would be nice to say something about the slide.

It’s an obvious landslide scar, and the slide later threatened the freeway, which is why there’s been all that repair work going on along the old railroad grade. I don’t know how old the slide is, though. The street maps show a continuous street in 1967, which is suggestive if not definitive.

See video of the slide and the work being done to mitigate it: part 1part 2

Thanks Andrew — although the slide repair now underway is a bit away from the area where the road itself is missing. A few months ago, I walked along the old Sac Northern ROW between Florence and the Broadway Terrace onramp right through the construction project (the fence on the south side had been knocked down) — but wasn’t able to make it all the way to Broadway Terrace because we belatedly discovered there was a security guard in a car parked at the north end.

One more comment; I recently spoke to the owners of a bunch of lots along the missing section of Sheridan, and they said there was no slide in this location — the road was apparently never built because of the slope. They reviewed City records and hired engineers and others to investigate the site before drawing that conclusion.

[Neal, thanks for this research. It’s still odd that street maps used to show a street existing there. Next step is reviewing aerial photos, I guess.]

Hi, Andrew: I’m Maureen Kennedy, a realtor-broker in Piedmont. Also the daughter-in-law of David Alt (of Roadside Geology fame). I just came across your blog while googling Wildwood Creek–I sold the home at the top at 3 WW Gardens, and now am listing the house at the bottom at 89 Oakmont. I think I checked all options, but don’t see a walk down that creek bed? Thanks, Maureen

[Maureen, pleased to hear from someone of your distinguished family! I haven’t ventured much into Piedmont, but that looks like quite a dramatic little gulch. However, there is no public right of way along the creek so I won’t be walking there — or if I do I won’t be talking about it here.]

I was astonished to learn, on June 30, that About.com decided to terminate my contract after 17 years of building the geology.about.com site. At the same time, my wife and I had decided to move to a new place in Oakland, and that came down faster than we’d anticipated. So this month has been an unusual one, and until today I’ve done almost nothing fun. But the good part is that I have more time to work on this site.

I’m sorry to hear that, Andrew. Unless you are excited about the change! Still loving your blog. Also I had forgotten about my question at the the top of this page. We ended up buying in Estudillo Estates, so here’s hoping those earthen dams hold up!

Sorry to hear about about.com. You are a relentlessly upbeat and resourceful person. I hope/believe you’ll move on successfully. Maybe guided tours and multimedia applications showcasing your knowledge like Joel Pomerantz has built some business around in San Francisco? Anyway, I’m glad I have found your site and am looking forward to following your posts.

Suggestion: Google “Mish” Mike Shedlock. He spun out his own blog — in his case, a financial blog — and ran his own advertisers. You might consider doing the same. Right now, you have a following, mostly highly local to the west coast. Get your advertisers from there, especially restaurants around the area [people on geotreks get hungry] and bed-and-breakfasts… and I expect you’ll do quite well.

I’m a grad student at San Jose State in geology and I live in Hayward. I am SO excited to find this blog and do some of the walks you have posted. Some of my fellow students or alumns live in Oakland and I hope we can all make your next walk. Thank you for making where I live infinitely more exciting! Heather

I will be delivering a talk at the next Nerd Nite East Bay meeting, on 28 December, tentatively titled “Diversity in Deepest Oakland: Rocks of the Town.” I will make the case that, square mile for square mile, Oakland is the most lithologically diverse city in America. If I can squeeze it in, I hope to ponder several different nerdy thoughts about rocks in general.

Nerd Nite East Bay (eastbay.nerdnite.com) happens the last Monday of the month at Club 21, a short stroll from the 19th Street BART station. Bring your laser pointer.

Thank you for your wonderful blog and for all the free lessons!
I have a question about a rock formation I saw yesterday in Redwood Regional Park. Along the creek trail there is a heavily eroded embankment that undercuts several large trees, and exposes the bare rock below. The rocks have a really interesting structure, with lots of round, layered structures. I have browsed back through lots of your posts, but have yet to see anything similar. Could you perhaps comment on this rock, or point me to a post which features a similar formation?

I am delivering a talk at the Oakland Museum of California the night of Friday March 18, in connection with the “Unearthed: Found + Made” exhibit, where I will “discuss the paradox of considering stones simultaneously as artworks and as geological specimens.” The strange intersection of natural objects and the categories into which we persist in arranging them has tickled my mind for many years, and I’m looking forward to this improvizational presentation in words and exhibits (including some of my own pet rocks). Details here.

On Monday 4 July I’ll be accompanying the oaklandtrails.org walk up Sausal Creek, from Dimond Park to the Chabot Observatory. Starts at 8:30 in the morning. Free. Details at http://oaklandtrails.org/hiking-tours/

many years ago we fond on our property in Vermont quartz Crystals.
the largest is 40lb, 20lb,5lb and some smaller.my question is
what can I do with them (other than using them as door stops)
do they have any marketable use?
would you please point me to someone who could help me out.
thank you very much,
Johanna

Johanna, I have always believed that the best use for objects like these is in a classroom or nature center, where young people can fall in love with them. The second-best use is to place them where the public can enjoy them. Without seeing your crystals, all I can suggest is to find your nearest rock shop and show the owners your best specimen.

Mineral specimens in museums and rock shops come from small mines all over the world. The odds are that your crystals aren’t valuable, just interesting.

Hi, been enjoying this site a lot, it has proved to be very useful in an ongoing project of mine: to incorporate native and local materials in pottery making. Some of the rocks around here make wonderful glazes. However, it is hard to know the proper formulations with regards to durability and food safety without analyses of the materials. I’ve googled without much success; happen to know if any group has that sort of information on record? And I hope my philosophy of utilizing the geology doesn’t conflict with yours of admiring it!

Of course, Oakland Heritage Alliance is much concerned with the fate of the old Club Knoll, a fine 1920s building later used as an officers’ club. Suncal proposes to move the structure. But I am writing you in case you are interested in the document’s words about geology and soils and rocks.

They are planning a lot of grading and sculpting of the huge site. So the SEIR includes a geo map and attends to lots of issues around Rifle Range Creek, what they plan to do with it, and how they are addressing various steep slopes, hills, ridges, seismic problems and grading.

Of course the public is invited to comment. But in any case you might find it interesting reading, and you might even want to contact the Suncal guys and walk around in there before they start moving rock around. There was previous fill and reconfiguration, when the navy was there, of course. But perhaps parts of the hillier areas haven’t been so much modified.

Anyhow, I know you like maps, and there are a bunch of them in the documents. Links below:

On Aug 29, 2016, at 5:26 PM, Klein, Heather wrote:

Dear Interested Parties,

The purpose of this e-mail is to let you know that the Draft Supplemental Environmental Impact Report (Draft SEIR) for the Oak Knoll Mixed Use community Plan Project is available.